A police spokeswoman said the three people were hunting on private land, using an off-road quad bike.
"They have gone off the side of a steep hill, landing in water. One person went to a nearby residence to raise the alarm and call for help.
"We were notified of the crash at around 1.50am."
She said both women had broken ribs and one also had the leg injury.
"Although police attended, because this crash took place on private land it is not a police matter."
The steep terrain meant that the helicopter was unable to land and the women had to be winched. One of the women had serious leg injuries and the other had chest and facial injuries.
McAuliffe said the women, aged 37- and 39-years-old, did not arrive at Nelson Hospital until closer to 5am - meaning they were in exposed and cold condition for hours.
"There was difficulty getting the women to the road because of the terrain."
However, other local residents had rushed to the scene to help, he said.
A Nelson Marlborough DHB spokeswoman said the 37-year-old was in a stable condition at Nelson Hospital and the 39-year-old had been discharged this morning.